Break the rules of genetics and get her pregnant

From Create Your Own Story

You quickly shift into the master and change her body so that dog sperm can impregnate her, then return to Thor. You know that she will soon be the mother to many, many litters of your pups, then you can take her again and again. All of your pups turn out to be male, and with the same package as their father, creating a whole new breed of dog that is meant solely for pleasure. Only after a few years is it found that these dogs also have a chance at impregnating human females. You have created a new race of dogs, and have a breeding slut that will give birth to as many of them as you want, so long as she can feel your twin cocks filling her whenever she can.

END?